Staple for blind stitching



May 1C, 1939. A. H. MAYNARD STAP-LE FOR BLIND STITCHING Filed Oct. 8,1936 Patented May 16, 1939 UNITED STATES PATENT '.OFFlC STAPLE FOR BLINDSTITCHING Application Qctober 8, 1936, Serial No. 104,688

3 Claims.

This invention relates to an improved method of and fastener forattaching together overlapped layers or plies of material with a blindstitch.

One of the objects of the invention is to provide a method of fasteningtogether layers of material whereof a metal fastener is caused to pierceonly certain of a plurality of the layers or plies with its legsclinched in the material to form a blind stitch.

Another object of the invention is to provide a self-clinching metalfastener so constructed A that its legs will be bent inwardly as theyare driven into the work to clinch them in the material and form a blindstitch. l

Still another object of the invention is to provide a self-clinchingstaple having portions of its legs adjacent their free ends bentinwardly toward each other and the ends of the legs beveled inwardlywith respect to the bent portions.

Further objects of the invention are set forth in the followingspecification which describes the improved method and a preferred formof construction of the fastener,A by way of example, as illustrated bythe accompanying drawing. In the drawing:

Fig. 1 is an enlarged perspective view of a stick or refill pack ofstaples incorporating the novel features of the present invention;

Fig. 2 is an enlarged view of a single staple showing the inwardly bentterminal portions of its legs and their beveled ends;

Fig. 3 is a part-sectional view of a portion of a staple-applyingimplement showing the relationship of the staple to the work at thebeginning of the stitching operation;

Fig. 4 is a view similar to Fig. 3 showing the staple partially driveninto the laminated material and illustrating the initial deformation ofits legs caused by the driving;

Fig. 5 is a view similar to Figs. 3 and 4 showing the` staple completelydriven and its legs clinched in the material to form a blind stitch; and

Fig. 6 is a perspective view of the laminated material showing thedriven staple therein.

Although the improved method `and fastener of the present inventionmay'have other applications, they are particularly adapted for fasteningthe cuffs to the legs of apparel trousers. The cuffs are originallystitched or tacked to the legs of 'the trousers with thread and when thegarment is to be cleansed the stitching is cut or ripped to permit thefolded parts to be brushed.

To save the time required to restitch the cuffs to the trouser legs,cleansers have adopted the practice of reattaching the cuis with smallsafety pins inserted through the inside of the leg of the trousers andthrough several plies of the cloth of the cud, but Without piercing allof y the plies so that the pin is not visible from the outside.. Thispractice saves time over the old practice of stitching but requires theuse of safety pins liable to become uniastened and lost. In accordancewith the present invention the cuffs may be attached to the trouser legswith greater economyof time and with relatively inexpensive fastenerswhich form a blind stitch. The improved method comprises providing awire staple having a crossbar and depending legs with portions of thelegs adjacent thecrossbar formed straight and parallel and theirterminall portions or free ends inclined inwardly toward each other. Theends or points of the staple legs are beveled inwardly with respect tothe bent portions to form a series of angularly related sections in thelegs which converge in the plane of the staple from the straightparallel portions to the pointed ends. Due to-the bent terminal portionsof the staple legs the ends or points pierce the work inwardly from theends of the crossbar. Application of a driving forceon the crossbarcauses the legs to simultaneously penetrate the work and to be bentinwardly toward each other .from their points of joinder with thecrossbar; this eiiect being due to the engagement of the ends of' thelegs with the work inwardly of the ends of the crossbar and the angularrelation of the terminal portions of the legs, as indicated .in Fig. 4

of the present drawing.

Continued application of the driving force on the crossbar of the staplecauses the legs to penetrate the work until they have been so deformedthat their terminal portions move inwardly toward each other at rightangles to the direction of the driving force and finally -bend upwardlytoward the crossbar. The angle of the bent terminal portions of the legswith respect to their straight parallel portions is preferably such thatthe ends or points of the legs will penetrate all of the cloth plies ofthe cuff except the last or lowermost one'before they move horizontallydue to the inward bending of the legs; and this angle maybe varied toaccommodate work of any particular type or thickness. Moreover, thebevels on the outer sides of the legs have an important function inassisting the inward deflection of the legs and preventing the ends frompiercing through the last layer. It will be observed by reference to thedrawing that the work is supported on a rest or platen 9 forming thebase 0f the stapling implement and slightly concaved on its upper face.The. cloth is compressed against this rest and the lower layer willtherefore offer considerable resistance to penetration by the legs' ofthe staple so that the bevels at the ends thereof will slide across thematerial until the points are turned upwardly. That is to say, after thelegs have been bent or deflected yt0 such a degree thatythey no longerpenetrate the work the application of the driving force causes the endsof the legs to be bent upwardly and clinched in the material to form ablind stitch as indicated in Fig. 5.

The improved staples may be preformed in the process of manufacture orthey may be shaped as they are driven in any suitable implement providedwith means for this purpose. As illustrated in the drawing, the staplesare preformed and connected in parallel, contiguous relationship bymeans of a suitable adhesive to provide a stick of any desired lengthwhich serves as a refill for the stapling implement. Each staple of thestick has a crossbar 2 with opposite depending legs 3 extending at rightangles to the crossbar. A portion of the legs 3 adjacent the crossbar 2are straight and parallel while the lower terminal portions 4 of thelegs are bent inwardly toward each other. 'I'he angle of inclination ofthe inwardly-directed end portion 4 with respect to the parallel portionof each leg 53, indicated at a in Fig. 2, may be varied between thirtyand sixty degrees to accommodate different thicknesses of work.` It hasbeen found that a staple will properly operate on the cuffs of trousersof average textile material when this angle is approximately fortydegrees.

In accordance with a further feature of the present invention the endsor points of the legs are beveled inwardly toward each other asindicated at 5. points are beveled on opposite sides preferably to forman angle, indicated at b, of approximately thirty degrees so that thelower sides of the points of the staple legs project at an angle,indicated at c, of twenty degrees with respect to theI work. It will beunderstood, however, that the bevels 5 may be of greater or less angularinclination or may extend wholly from the outside to the inside of thestaple leg in one continuous plane.

'I'he essential elements of an implement for driving the preformedstaples, preferably a handoperated tool or a pair of pliers, areillustrated in Figs. 3 and 4 of the drawing as comprising a head 6, acore 'l for supporting a stick of the staples, means, not herein shown,for feeding the staples into the head, and a work-rest or platen 9. Thework w is held between' the head 6 and platen 9 and the foremost stapleof the stick is adapted to be driven into the work by a staple-driver 8mounted for reciprocation in the head.

As herein illustrated, the ends or In attaching the cuffs to the legs ofa pair of trousers, or in fastening together any other overlapped layersof material, the work is rst compressed between the head 6 and platen 9.rI'he stick of staples supported on the core 'l is fed therealong bysuitable means to advance the foremost staple into a throat at the endof the head to be driven into the work by the stapledriver 8. Asexplained above, the staple legs 3 are automatically bent inwardlytoward each other as they are driven into the work w and inuenced bytheir beveled ends to cause them to penetrate only a predeterminednumber of the layers or plies of cloth and to be self -clinched by thedriving force applied thereto.

The improved method of blind stitching and the novel form of fastenertherefor having now been described, it will be observed that theinvention provides for stitching or tacking the cuffs to the legs oftrousers with a blind stitch,

be made in its shape and the angular relationship of the differentportions of the staple legs without departing from the spirit or scopeof.

the invention. Therefore, without limiting myself in this respect, Iclaim:

l. A self -clinching staple of readily deformable wire for forming ablind stitch comprising a crossbar and depending legs having parallelp0rtions adjacent the crossbar, straight portions adjacent their freeends inclined inwardly tpward each other, and the ends beveled to directthe points inwardly toward each other when the staple is applied to thework. 1

2. A self-clinching staple of readily deformable wire for forming ablind stitch comprising a crossbar and depending legs having parallelportions adjacent the crossbar extending at right angles thereto andportions adjacent their free ends inclined inwardly from the parallelportions at an angle greater than thirty degrees and less than sixtydegrees.

3. A self-clinching staple of readily deformable wire for forming ablind stitch comprising a crossbar and depending legs having parallelportions adjacent the crossbar extending at right angles thereto, andportions adjacent their free ends bent inwardly from the parallelportions at an angle greater than thirty degrees and less than sixtydegrees with the ends of the legs beveled to direct the points inwardlytoward each other when the staple is applied to the work.

ARTHUR H. MAYNARD.

